This invention relates to a probe for conditioning a fluid sample to be analyzed having one or more undesirable components entrained therein. In particular, it relates to a system that can very precisely cool the sample to remove just the undesirable components through condensation. In a process gas stream it is often desirable to know the concentration of one or more compounds that make up the process stream. This concentration knowledge allows feedback to be sent to an operator(s) or equipment in the process that can make changes based on the information obtained. For example, in a Claus sulfur recovery process H2S and SO2 are reacted to produce elemental sulfur and water. By analyzing the concentration of H2S leftover in the tail-gas from the reaction, feedback can be provided that can be used to adjust the amount of H2S being supplied to the reaction. However, analysis of the tail-gas is complicated by the presence of elemental sulfur vapor which distorts the readings obtained from a spectrometer, and which can solidify on the analyzing equipment's interior surface. Therefore it is an object of the present invention to provide an in-situ probe that can remove sulfur vapor from a process gas stream by condensing the vapor into a liquid such that it precipitates into the process stream before it can accumulate on the analyzing equipment's interior surface.